USB speeds terrible

[perdomot]

I copied a folder with 590MB of photos to a thumbdrive and averaged a transfer rate of about 300KB/s. I tested an avi file of 170MB and got 2.9MB/s. This was with both the front and rear usb ports. When I took the drive to work and copied the pics onto the pc, it took less than a minute to copy them all whereas my home pc took several minutes to write the folder to the drive. I have a 780G mobo and the amd average tested usb speed is supposed to be around 30MB/sec:
http://www.techreport.com/articles.x/14261/12

Anyone got any ideas why the slow transfer speeds? I'm sure its not the drive.

 

[taltamir]

pictures are small writes... the bigger the write, the more "sequential" it is, the faster it goes.

You might have heard of the stutter problem with SSDs? that is because MLC chips just write small files really really slowly. Well, an intel X25 has ten of those chips in internal raid0. your thumb drive has TWO of those chips, and a stupid controller, so you get 300KB/s writes. It could have actually been even worse.

The solution is to make one big zip or rar file from them before copying it over, then it will write at the 2.9MB/s speed. and you can extract them on the destination computer.

 

[alcoholbob]

Read speed of a hard drive and USB drive are not equal. The review you mentioned tests the read and write speed of a mechanical hard drive.

Copying to, and copying from a USB drive are completely opposite. The first, you are bottlenecked by the USB drive's read & write speed. With the latter, the hard drive is much faster with read & write so it's file create time is much lower.

 

[tcsenter]

In the first instance, you were writing to flash memory drive. At work, you were reading from flash memory and writing to a hard disk. Flash memory has better read performance than write performance (for that matter, all storage devices/mediums do, but a lot of flash drives have awful write performance compared to reads).

Try copying the files from flash drive to a temp directory on the PC with the 780G mobo. Should get results comparable to what you experienced on the work computer.

 

[RebateMonger]

Originally posted by: tcsenter
Flash memory has better read performance than write performance (for that matter, all storage devices/mediums do, but a lot of flash drives have awful write performance compared to reads).

This.

 

[perdomot]

Thanks for the feedback:
taltamir: The zip trick worked so I'll be doing it that way. Thanks a lot!

I do know that reads and writes are usually different but I had no idea that the writes on usb drives was so bad. I hardly ever use mine and my external hdd for backups uses esata so I hadn't tested it out. Is 3MB/s about normal speed for most usb drives?

 

[perdomot]

http://www.xbitlabs.com/articl...-roundup_15.html#sect1

I found the above review at one of the sites I visit and saw that the large number of small files does copy much slower than it reads. I also noticed that the slowest drive was still much faster than my Centon Datastick Pro by a factor of 5x. I'm going to try copying the files at work back onto the drive today to see how long it takes.